Sustainable Stabilization of Earth Blocks Using Ground Flaxseed and Flax Fibers: A Bio-Based Alternative to Cement and Lime

Abstract

Earthen construction has re-emerged as a sustainable building method due to its local availability, excellent thermal performance, low energy requirements, and recyclability. However, traditional stabilized earth blocks (SEBs) often face limitations such as water sensitivity, shrinkage, and erosion. To mitigate these issues, various stabilizers—such as cement, lime, agro-industrial by-products, and natural fibers—have been investigated. While chemical stabilizers like cement and lime enhance the strength and durability of SEBs, they also significantly increase embodied energy and reduce overall eco-efficiency.  This study explores ground flaxseed as a sustainable, bio-based alternative stabilizer, evaluating its performance at 2% of the soil's dry mass in comparison to conventional cement and lime stabilizers used at 10%. Additionally, the influence of flax fibers on SEB performance is assessed across five inclusion rates (0%, 0.25%, 0.5%, 0.75%, and 1%) to identify the optimal proportion for improving mechanical strength and thermal performance.  The overarching goal is to develop an environmentally friendly SEB formulation that preserves or enhances structural integrity and thermal efficiency while minimizing environmental impact.